<!DOCTYPE html>
<html>
<head>
    <meta charset='utf-8'>
    <meta http-equiv='X-UA-Compatible' content='IE=edge'>
    <title>抽奖</title>
    <!--js版的圆盘抽奖，可以动态奖品-->
    <meta name='viewport' content='width=device-width, initial-scale=1'>
    <!-- <link rel='stylesheet' type='text/css' media='screen' href='main.css'> -->
    <!-- <script src='main.js'></script> -->
    <script class="jquery library" src="js/jquery-1.8.2.min.js" type="text/javascript"></script>
	<script type="text/javascript" src="js/jQueryRotate.2.2.js"></script>
    <style>
        #container {
            height: 520px;
            width: 520px;
        }
        .pointer {
            color: red;
            position: absolute;
            top: 210px;
            left: 204px;
        }
        #wheelcanvas {
            transform-origin: center center;
        }
    </style>
</head>

<body>
    <div id="container">
        <canvas id="wheelcanvas" height="420" width="420"></canvas>
        <img id="fen-img" src="images/1.jpg" width="30" height="30" hidden="true">
        <img id="zuliao-img" src="images/1.jpg" width="30" height="30" hidden="ture">
        <img id="baowen-img" src="images/1.jpg" width="30" height="30" hidden="true">
        <img id="yundou-img" src="images/1.jpg" width="30" height="30" hidden="true">
        <img id="ganlan-img" src="images/1.jpg" width="30" height="30" hidden="true">
        <img id="yusan-img" src="images/1.jpg" width="30" height="30" hidden="true">
        <div class="pointer">抽奖</div>
        <!-- <img id="start" class="pointer" src="images/disc-rotate.gif" width="100" height="100"> -->
    </div>
</body>
<script type="text/javascript">
    var turnplate = {
        restaraunts: [],			//大转盘奖品名称
        colors: [],					//大转盘奖品区块对应背景颜色
        outsideRadius: 192,			//大转盘外圆的半径
        textRadius: 155,			//大转盘奖品位置距离圆心的距离
        insideRadius: 68,			//大转盘内圆的半径
        startAngle: 0,				//开始角度
        bRotate: false				//false:停止;ture:旋转
    };

    $(document).ready(function () {
        //动态添加大转盘的奖品与奖品区域背景颜色
        turnplate.restaraunts = ["20积分", "足疗机", "20积分", "保温杯", "20积分", "手持式电熨斗", "20积分 ", "橄榄油", "20积分", "晴雨伞"];
        turnplate.colors = ["#FFF4D6", "#FFFFFF", "#FFF4D6", "#FFFFFF", "#FFF4D6", "#FFFFFF", "#FFF4D6", "#FFFFFF", "#FFF4D6", "#FFFFFF"];
        var rotateTimeOut = function () {
            $('#wheelcanvas').rotate({
                angle: 0,
                animateTo: 2160,
                duration: 8000,
                callback: function () {
                    alert('网络超时，请检查您的网络设置！');
                }
            });
        };

        //旋转转盘 item:奖品位置; txt：提示语;
        var rotateFn = function (item, txt) {
            var angles = item * (360 / turnplate.restaraunts.length) - (360 / (turnplate.restaraunts.length * 2));
            if (angles < 270) {
                angles = 270 - angles;
            } else {
                angles = 360 - angles + 270;
            }
            $('#wheelcanvas').stopRotate();
            $('#wheelcanvas').rotate({
                angle: 0,
                animateTo: angles + 1800,
                duration: 5000,
                callback: function () {
                    //中奖提示
                    alert(txt);
                    turnplate.bRotate = !turnplate.bRotate;
                }
            });
        };

        $('.pointer').click(function () {
            if (turnplate.bRotate) return;
            turnplate.bRotate = !turnplate.bRotate;
            //获取随机数(奖品个数范围内)
            var item = rnd(1, turnplate.restaraunts.length);
            //奖品数量等于10,指针落在对应奖品区域的中心角度[252, 216, 180, 144, 108, 72, 36, 360, 324, 288]
            rotateFn(item, turnplate.restaraunts[item - 1]);
            console.log(item);
        });
    });

    function rnd(n, m) {
        n = 1;//最小随机数
        m = 100;//最大随机数（概率范围最大值）
        //最大数数不超过最大随机数
        var ransluck = [50, 60, 65, 70, 75, 80, 85, 90, 95, 100];//概率为比自己小的第一个数之间的差
        var randoms = Math.floor(Math.random() * (m - n + 1) + n);
        if (randoms <= ransluck[0]) {
            var random = 1;
        }
        else if (randoms <= ransluck[1]) {
            var random = 2;
        }
        else if (randoms <= ransluck[2]) {
            var random = 3;
        }
        else if (randoms <= ransluck[3]) {
            var random = 4;
        }
        else if (randoms <= ransluck[4]) {
            var random = 5;
        }
        else if (randoms <= ransluck[5]) {
            var random = 6;
        }
        else if (randoms <= ransluck[6]) {
            var random = 7;
        }
        else if (randoms <= ransluck[7]) {
            var random = 8;
        }
        else if (randoms <= ransluck[8]) {
            var random = 9;
        }
        else if (randoms <= ransluck[9]) {
            var random = 10;
        }
        //alert(randoms);
        //alert(random);
        return random;

    }


    //页面所有元素加载完毕后执行drawRouletteWheel()方法对转盘进行渲染
    window.onload = function () {
        drawRouletteWheel();
    };

    function drawRouletteWheel() {
        var canvas = document.getElementById("wheelcanvas");
        if (canvas.getContext) {
            //根据奖品个数计算圆周角度
            var arc = Math.PI / (turnplate.restaraunts.length / 2);
            var ctx = canvas.getContext("2d");
            //在给定矩形内清空一个矩形
            ctx.clearRect(0, 0, 422, 422);
            //strokeStyle 属性设置或返回用于笔触的颜色、渐变或模式  
            ctx.strokeStyle = "#FFBE04";
            //font 属性设置或返回画布上文本内容的当前字体属性
            ctx.font = '16px Microsoft YaHei';
            for (var i = 0; i < turnplate.restaraunts.length; i++) {
                var angle = turnplate.startAngle + i * arc;
                ctx.fillStyle = turnplate.colors[i];
                ctx.beginPath();
                //arc(x,y,r,起始角,结束角,绘制方向) 方法创建弧/曲线（用于创建圆或部分圆）    
                ctx.arc(211, 211, turnplate.outsideRadius, angle, angle + arc, false);
                ctx.arc(211, 211, turnplate.insideRadius, angle + arc, angle, true);
                ctx.stroke();
                ctx.fill();
                //锁画布(为了保存之前的画布状态)
                ctx.save();

                //----绘制奖品开始----
                ctx.fillStyle = "#E5302F";
                var text = turnplate.restaraunts[i];
                var line_height = 17;
                //translate方法重新映射画布上的 (0,0) 位置
                ctx.translate(211 + Math.cos(angle + arc / 2) * turnplate.textRadius, 211 + Math.sin(angle + arc / 2) * turnplate.textRadius);

                //rotate方法旋转当前的绘图
                ctx.rotate(angle + arc / 2 + Math.PI / 2);

                /** 下面代码根据奖品类型、奖品名称长度渲染不同效果，如字体、颜色、图片效果。(具体根据实际情况改变) **/
                if (text.indexOf("M") > 0) {//流量包
                    var texts = text.split("M");
                    for (var j = 0; j < texts.length; j++) {
                        ctx.font = j == 0 ? 'bold 20px Microsoft YaHei' : '16px Microsoft YaHei';
                        if (j == 0) {
                            ctx.fillText(texts[j] + "M", -ctx.measureText(texts[j] + "M").width / 2, j * line_height);
                        } else {
                            ctx.fillText(texts[j], -ctx.measureText(texts[j]).width / 2, j * line_height);
                        }
                    }
                } else if (text.indexOf("M") == -1 && text.length > 6) {//奖品名称长度超过一定范围 
                    text = text.substring(0, 6) + "||" + text.substring(6);
                    var texts = text.split("||");
                    for (var j = 0; j < texts.length; j++) {
                        ctx.fillText(texts[j], -ctx.measureText(texts[j]).width / 2, j * line_height);
                    }
                } else {
                    //在画布上绘制填色的文本。文本的默认颜色是黑色
                    //measureText()方法返回包含一个对象，该对象包含以像素计的指定字体宽度
                    ctx.fillText(text, -ctx.measureText(text).width / 2, 0);
                }

                //添加对应图标
                if (text.indexOf("分") > 0) {
                    var img = document.getElementById("fen-img");
                    img.onload = function () {
                        ctx.drawImage(img, -15, 10);
                    };
                    ctx.drawImage(img, -15, 10);
                } else if (text.indexOf("足疗") >= 0) {
                    var img = document.getElementById("zuliao-img");
                    img.onload = function () {
                        ctx.drawImage(img, -15, 10);
                    };
                    ctx.drawImage(img, -15, 10);
                }
                else if (text.indexOf("保温") >= 0) {
                    var img = document.getElementById("baowen-img");
                    img.onload = function () {
                        ctx.drawImage(img, -15, 10);
                    };
                    ctx.drawImage(img, -15, 10);
                }
                else if (text.indexOf("电熨斗") >= 0) {
                    var img = document.getElementById("yundou-img");
                    img.onload = function () {
                        ctx.drawImage(img, -15, 10);
                    };
                    ctx.drawImage(img, -15, 10);
                }
                else if (text.indexOf("橄榄") >= 0) {
                    var img = document.getElementById("ganlan-img");
                    img.onload = function () {
                        ctx.drawImage(img, -15, 10);
                    };
                    ctx.drawImage(img, -15, 10);
                }
                else if (text.indexOf("雨伞") >= 0) {
                    var img = document.getElementById("yusan-img");
                    img.onload = function () {
                        ctx.drawImage(img, -15, 10);
                    };
                    ctx.drawImage(img, -15, 10);
                }

                //把当前画布返回（调整）到上一个save()状态之前 
                ctx.restore();
                //----绘制奖品结束----
            }
        }
    }
</script>
</html>